Using the PNG algorithm to save a .mat file

Hello,

I have a (382x486) matrix and I want to save it in a compressed form. If I save this matrix as a png image I get a very good compression (compared to the original matrix saved in .mat format alone). I am wondering if there is someway that I can use the algorithm used in PNG to compress the file in .mat format.

Thank you.

Answer 1

[Image Analyst]

It does not look like it according to the help. It just uses some internal compression scheme and you have no control over that except to turn it off completely. But with an image that tiny, why do you even care?

Answer 2

[Guillaume]

The compression method that PNG uses is the well established deflate algorithm. This is the same algorithm that gzip uses and is also the most commonly used compression method used by zip, both of which are standard matlab functions.

The most commonly used library implementation is zlib for which precompiled dll are available. This could be used in matlab via loadlibrary if you wanted to compress something that is not a file. If you want to make your life easy, use gzip.